It's fairly clear it will simultaneously have upside and downside.
Upside: more award availability.
Downside: costs more.
If you are points rich and have an inflexible schedule, the upside outweighs the downside. If you are points poor and have a flexible schedule, the downside outweighs the upside as Qantas push more seats into this new tier.
However, market dynamics will be the ultimate determinant of where it goes. At the end of the day, airlines need to fill seats in premium cabins. If When we get another black swan event in the airline industry that craters demand, we will see cash fares come down and classic award availability open up because people won't even be willing to pay the newer higher tier award price. Indeed, while we haven't seen it with Qantas yet, classic award availability between Australia and North America has never been better due to United having heaps of capacity and not enough people willing to pay. They regularly have 9 award seats in J available on multiple routes across most of the year, as long as you are willing to wait until the last couple of weeks to book.
Maybe Turkish's entry into Australia will open up a similar competitive dynamic onto the European routes, especially when it begins to offer 1 stop connectivity. Though Qantas have a lot less capacity to Europe, so the risk of having empty seats is going to be lower — their vulnerability to competition is mostly on their Asian and North American routes where they fly a lot of planes.